4221856671437 has 2 divisors, whose sum is σ = 4221856671438. Its totient is φ = 4221856671436.

The previous prime is 4221856671397. The next prime is 4221856671443. The reversal of 4221856671437 is 7341766581224.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3367247020036 + 854609651401 = 1835006^2 + 924451^2 .

It is a cyclic number.

It is not a de Polignac number, because 4221856671437 - 2⁸ = 4221856671181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4221856671337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2110928335718 + 2110928335719.

It is an arithmetic number, because the mean of its divisors is an integer number (2110928335719).

Almost surely, 2^{4221856671437} is an apocalyptic number.

It is an amenable number.

4221856671437 is a deficient number, since it is larger than the sum of its proper divisors (1).

4221856671437 is an equidigital number, since it uses as much as digits as its factorization.

4221856671437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13547520, while the sum is 56.

The spelling of 4221856671437 in words is "four trillion, two hundred twenty-one billion, eight hundred fifty-six million, six hundred seventy-one thousand, four hundred thirty-seven".